Original subtitles

NARRATOR: Poland's Owl Mountains, deep in the Silesian forests,

hide one of World War II's greatest secrets.

hide one of World War II's greatest secrets.

- Riese is one of the most

massive construction projects ever.

massive construction projects ever.

NARRATOR: Here you'll find the home

of the Third Reich's largest investment:

a gigantic underground complex called Riese...

a gigantic underground complex called Riese...

German for Giant.

- (speaking other language)

NARRATOR: Recently, in Prague, we discovered

new, top secret documents, which help shed new light

on the mysteries of Riese.

ALEXANDRA: There are all sorts of aspects which we haven't discovered.

ALEXANDRA: There are all sorts of aspects which we haven't discovered.

- (speaking other language)

NARRATOR: Could Riese have changed the course of history?

Were the Nazis creating a secret superweapon

Were the Nazis creating a secret superweapon

to save them from imminent defeat?

ALEXANDRA: There was a uranium mine near Riese.

NARRATOR: This castle was home to the final

NARRATOR: This castle was home to the final

hidden project of Europe's bloodiest agent...

..Germany's Fuhrer...

..Germany's Fuhrer...

Adolf Hitler.

- (shouting in German)

- (shouting in German)

NARRATOR: Was Riese meant to set the stage for the final stand

of Hitler and his high command?

Underground tunnels.

Nuclear bunkers.

Architectural madness.

Architectural madness.

Lavish headquarters.

For dictators, the cost did not matter.

For dictators, the cost did not matter.

Only their desires, power,

and security.

and security.

What secrets hide in these grand structures?

GUY: By 1943, Hitler is in a desperate situation.

GUY: By 1943, Hitler is in a desperate situation.

The war is going completely the wrong way for him.

- Germans started to fear that Germany might lose the war,

- Germans started to fear that Germany might lose the war,

particularly after Stalingrad and the Battle of Kursk,

because these were momentous losses.

NARRATOR: Additionally, the Germans were further weakened

NARRATOR: Additionally, the Germans were further weakened

by the Allied bombing of Hitler's top secret flying bomb

and ballistic missile factory.

These were his feared superweapons,

These were his feared superweapons,

with which he hoped to achieve military supremacy.

- He is being bombed, you know, day and night by the British,

- He is being bombed, you know, day and night by the British,

and, increasingly, the Americans.

NARRATOR: Furthermore, a covert operation by the Allies

effectively destroyed Germany's heavy water supply,

effectively destroyed Germany's heavy water supply,

a critical component in Hitler's pursuit of developing

an atomic bomb before the West.

A weapon he believed could turn the tide of war in his favour.

As his enemies drew ever closer,

secret quarters and command bunkers were built

all over occupied Europe to ensure Hitler's safety.

all over occupied Europe to ensure Hitler's safety.

- The most important bunker headquarters,

in the war itself, was the Wolf's Lair.

In a very remote part of the forest,

a very dark and dank area.

It was a vast area with gigantic bunkers,

It was a vast area with gigantic bunkers,

with seven metre-thick ceilings.

Area around the Wolfsschanze was mined,

at least 60,000 mines.

at least 60,000 mines.

After the war, it was very, very difficult to de-mine the area.

The mines were being cleared even in the 1960s.

NARRATOR: Even in the Wolf's Lair,

Hitler could not feel completely safe

from the advancing Soviet forces.

So the complex was abandoned in late 1944,

So the complex was abandoned in late 1944,

and destroyed in early 1945.

Hitler needed another, safer refuge.

Hitler needed another, safer refuge.

Desperate, he turned to his most trusted confidant

and longtime friend, Albert Speer.

and longtime friend, Albert Speer.

- Albert Speer was an architect, and Hitler liked him very much,

because Hitler thought of himself as an architect and an artist.

because Hitler thought of himself as an architect and an artist.

- Dictators have a tendency

to build very large scale projects,

to build very large scale projects,

which reflect their own megalomania and narcissism.

This is an attempt to glorify

This is an attempt to glorify

the dictator personally.

GUY: What Adolf Hitler was trying to do

was to make Germany the centre of the world...

was to make Germany the centre of the world...

..and he was also going to try and make Berlin

the centre of that new Germany: Germania.

So these were buildings built on a scale

So these were buildings built on a scale

that had never been seen before.

ALEXANDRA: Everything has to be bigger and better and shinier

and more important than any other capital city in the world.

This is to reflect both Hitler and his power,

This is to reflect both Hitler and his power,

but also the power of this 1,000-year Reich he's creating.

NARRATOR: In August 1943, with time running out,

Hitler and Speer jointly embarked on a top secret project

Hitler and Speer jointly embarked on a top secret project

to secure the future of the Third Reich.

It was an ambitious urban project.

The largest of its kind in the history of the Third Reich.

Hitler's new headquarters.

Hitler's new headquarters.

A hidden fortress.

A series of underground factories

for the development of top secret weapons.

It was codenamed Project Riese.

Was this project supposed to change the course of the war?

Only now, 80 years after it was built,

Only now, 80 years after it was built,

can the true scale and purpose of Adolf Hitler's last great secret

finally be revealed.

finally be revealed.

By September 1943,

the primary objective for Germany

was to find a secure location

to move their most valuable military projects

beyond the reach of the Allied Air Force.

- How do you protect yourself from these bombing raids?

One way was to move your production facilities

as far away as possible and another way was to put them underground.

as far away as possible and another way was to put them underground.

NARRATOR: And all over Europe, there are plenty of places

where Hitler can start burying his industrial facilities.

where Hitler can start burying his industrial facilities.

ALEXANDRA: The Riese Complex was considered to be one of those places

that was safe because it was out of the range

that was safe because it was out of the range

of the Allied bombers in 1943.

This was an area known as Silesia in Germany,

This was an area known as Silesia in Germany,

and it was quite agricultural, quite rural.

NARRATOR: And this location was not chosen by chance.

Although the area was green and lush,

Although the area was green and lush,

just beneath the surface was a major power supply.

- (speaking other language)

NARRATOR: This immense level of power

signifies that Riese wasn't just a headquarters,

signifies that Riese wasn't just a headquarters,

but something much more sophisticated.

GUY: Hitler and his munitions boss, Albert Speer,

GUY: Hitler and his munitions boss, Albert Speer,

they look at the Riese project, and that's in the Owl Mountains,

and they think, "What we can do here is to build something really big,

and they think, "What we can do here is to build something really big,

"something impressive, something seriously useful."

ALEXANDRA: And there was this mountainous area,

ALEXANDRA: And there was this mountainous area,

and the idea then was developed that you could dig

into these mountains and create these huge, huge

underground complexes that would be completely hidden from above.

underground complexes that would be completely hidden from above.

ADRIAN: Concealment is also important.

So in mountains, you can go into caves,

in forests you can go, you know, under the tree canopy.

in forests you can go, you know, under the tree canopy.

NARRATOR: But the construction of such a huge underground complex

would require vast resources and manpower.

would require vast resources and manpower.

How would this be sourced at a time of desperate military reversals

on the Eastern Front?

The mystery of Riese had been studied

The mystery of Riese had been studied

by Polish historian Lukasz Kazek for years.

- (Lukasz speaking other language)

NARRATOR: Using slave labour supplied by Albert Speer,

construction on the site began in earnest in late 1943,

construction on the site began in earnest in late 1943,

utilising the mountainous terrain to preserve its secrecy.

As workers toiled below ground on the tunnel complex,

As workers toiled below ground on the tunnel complex,

up above, the scene was set

by the magnificent Ksiaz Castle,

designed to be the Fuhrer's final headquarters

designed to be the Fuhrer's final headquarters

from which he'd lead Nazi Germany to final victory.

The castle itself had an excellent defensive position.

The castle itself had an excellent defensive position.

It's located on a high hill,

serving as a difficult fortification to conquer.

The castle was built in 1288

The castle was built in 1288

as a residence for Prince Bolko Swidnicki.

It served as a fortress, guarding the passage to town.

It served as a fortress, guarding the passage to town.

- (Bogdan speaking other language)

- (Bogdan speaking other language)

NARRATOR: This revelation is confirmed by a top secret microfilm

found in German archives, with a list of Hitler's headquarters.

found in German archives, with a list of Hitler's headquarters.

The Riese Facility, codenamed Rudiger,

was mentioned under the Roman numeral five.

It was to consist of a main building

and the Ksiaz Castle.

The map shows exactly the Riese Project area.

This would be where the highest dignitaries

and top command of the Third Reich would live,

having escaped Berlin.

Detailed plans of each floor

along with room layouts were drafted.

- (speaking other language)

NARRATOR: But a fascist regime's headquarters

required more than just beautiful rooms.

It must also have

It must also have

secure underground facilities and escape routes.

- (speaking other language)

NARRATOR: The project also involved an area

NARRATOR: The project also involved an area

of several square kilometres on the mountain slopes,

where additional underground tunnel networks were being built.

The huge complex was built on the massif

of Osowka and Wlodarz in the Owl Mountains.

There was another reason for choosing this location:

the abundance of forced labour close by.

- (Lukasz speaking other language)

- (Lukasz speaking other language)

NARRATOR: The Gross-Rosen concentration camp

was located only 60 km away,

was located only 60 km away,

and could therefore provide the majority of the workers.

ALEXANDRA: They were used to quarry heavy stone.

They were given absolutely no protection.

Very, very little food, and they were beaten.

Very, very little food, and they were beaten.

They were whipped. They were treated like, basically worse than animals.

GUY: This was a violent,

appalling, horrific place to work.

appalling, horrific place to work.

Believe you me, Riese is a place

that is constructed on human misery and death.

that is constructed on human misery and death.

- (man speaking other language)

- (man speaking other language)

ALEXANDRA: Around about 5,000 labourers are estimated

to have been killed in the project Riese complex,

to have been killed in the project Riese complex,

although the number could've been higher, we just simply don't know.

NARRATOR: The life expectancy of a worker on the project

was three months maximum,

was three months maximum,

and even that was only if one managed to escape

the bouts of typhoid which periodically swept the camp.

The workers' plight, as with so much else connected to the Riese project,

was shrouded in secrecy.

was shrouded in secrecy.

- So the construction of facilities like the Riese complex,

- So the construction of facilities like the Riese complex,

they will be state secrets of quite a high level.

VICTOR: Because now you have a lot of people in the area

VICTOR: Because now you have a lot of people in the area

where you're building your bunker, and you don't trust anyone.

And now you have an issue, because you need them,

And now you have an issue, because you need them,

but you cannot tell them everything.

NARRATOR: A German engineer

knew only a portion of the structure.

knew only a portion of the structure.

He'd have no clue that there were six complexes

being built in the Owl Mountains,

with a seventh beneath the Ksiaz Castle.

with a seventh beneath the Ksiaz Castle.

- (man speaking other language)

- (speaking other language)

- (speaking other language)

NARRATOR: Everything was unfolding rapidly.

They drilled tunnels, threw out excess material,

and immediately built a narrow gauge railway afterwards.

Even so, Hitler was dissatisfied with the rate of progress,

Even so, Hitler was dissatisfied with the rate of progress,

and, in April 1944,

demanded the engineers redouble their efforts.

demanded the engineers redouble their efforts.

- (speaking other language)

NARRATOR: There were huge silos near this place,

NARRATOR: There were huge silos near this place,

where Germans stashed building materials for concrete walls.

It was warmed up through heating pipes,

to keep the aggregate from clumping.

The entire project required enormous amounts of energy and steam.

Where did this energy come from?

Where did this energy come from?

This mysterious structure hidden in the forest in the Owl mountains

is the heart of the entire Riese project.

is the heart of the entire Riese project.

Explorers have been trying to solve

the mystery of this building for years.

According to some, it was supposed to be

According to some, it was supposed to be

the foundation of a nuclear reactor or missile launcher.

But the truth, as we can now reveal, is quite different.

- (Lukasz speaking other language)

NARRATOR: There was also the main plant, where they produced concrete,

which was then poured through a special chute,

which was then poured through a special chute,

and then pumped further through a shaft.

- (Lukasz speaking other language)

- (Bogdan speaking other language)

VICTOR: Nowadays, you can build a 70 square bunker,

with the modern technology,

and the modern equipment, in four weeks.

and the modern equipment, in four weeks.

And if you compare that to the Riese construction,

in one year, what they built,

nine kilometres, yeah, that's impressive.

nine kilometres, yeah, that's impressive.

It's a metro station in a mountain.

GUY: Riese is one of the most massive construction projects.

It's extraordinary when you think that as the war

It's extraordinary when you think that as the war

is going so badly for Hitler,

both him and Albert Speer can still put lots and lots of resources

into constructing this massive place.

into constructing this massive place.

It's kind of madness, really.

NARRATOR: With every step of the project

NARRATOR: With every step of the project

personally overseen by Albert Speer,

this wasn't just a project simply to securely hide Hitler.

Riese was a colossus...

Riese was a colossus...

something much larger.

But what, exactly?

FATHALI: Dictators are typically characterised

FATHALI: Dictators are typically characterised

by a number of psychological traits.

They are paranoid,

and they are conspiratorial in mindset.

and they are conspiratorial in mindset.

Seeing plots against them at every turn.

- (shouting in German)

FATHALI: Dictators lose touch with reality,

because they become insulated,

they become surrounded by a small number of people

they become surrounded by a small number of people

who are very afraid of them.

GUY: Hitler is probably the most

GUY: Hitler is probably the most

closely guarded man in the world.

Now, you've got to remember that the SS

was formed as his private bodyguard.

was formed as his private bodyguard.

So he's got hundreds of people,

maybe actually thousands of people personally guarding him.

NARRATOR: In addition to the usual security detail for the Fuhrer,

some local subdivisions were assigned to the area

to protect the castle and underground complexes.

to protect the castle and underground complexes.

Riese was a secret facility, so instead of typical watchtowers,

concrete reinforced guard posts and masking paint were used.

concrete reinforced guard posts and masking paint were used.

- (Bogdan speaking other language)

- (Lukasz speaking other language)

- And, yet, like so many other dictators in that position,

- And, yet, like so many other dictators in that position,

you get that, you know, the paranoia starting up,

and he's constantly worrying about his personal security.

and he's constantly worrying about his personal security.

NARRATOR: How great, in reality, was the threat

to Hitler's life during this critical phase of the war?

And how was he kept safe from would-be assassins?

And how was he kept safe from would-be assassins?

- Of course, there were a number of attempts

- Of course, there were a number of attempts

against him while he was in power.

The most famous attempt was the Wolfsschanze - the Wolf's Lair -

The most famous attempt was the Wolfsschanze - the Wolf's Lair -

by Claus Schenk von Stauffenberg,

who tried to leave a bomb in a conference room,

to try and assassinate Hitler.

to try and assassinate Hitler.

The bomb went off,

and Hitler was slightly injured, but it didn't actually kill him.

So he wasn't incorrect to be afraid for his life.

It wasn't totally beyond reason, but it did make him paranoid,

It wasn't totally beyond reason, but it did make him paranoid,

and in the hideouts he developed, there were always bunkers.

NARRATOR: After the Stauffenburg plot

NARRATOR: After the Stauffenburg plot

to kill Hitler in July 1944,

further very advanced architectural works

were carried out at Ksiaz Castle

were carried out at Ksiaz Castle

to create the safest and most secure

of all Hitler's hideouts.

- If you are trying to protect a target within a bunker,

- If you are trying to protect a target within a bunker,

it needs to be very strongly constructed.

We're now thinking about things like reinforced concrete,

concrete and steel, anti-gas doors...

concrete and steel, anti-gas doors...

..and other sort of harder materials,

which will protect you from penetration, from bombs.

NARRATOR: Shafts and tunnels directly beneath the castle

were created in order to ensure Hitler had a secure bunker

in case of a bombing raid or other form of direct attack,

in case of a bombing raid or other form of direct attack,

along with other escape and evacuation routes.

Hitler's bedroom at Ksiaz was one of the safest places to sleep

Hitler's bedroom at Ksiaz was one of the safest places to sleep

in the whole of the Third Reich.

- You could be having a nice little sleep,

and then suddenly there's an air raid warning,

and then suddenly there's an air raid warning,

and bombers are within less than one or two minutes away.

And what you can do is to go

50 metres below the ground, straightaway,

50 metres below the ground, straightaway,

and it's protected by all that rock and concrete and construction.

NARRATOR: An elevator shaft would lead

NARRATOR: An elevator shaft would lead

20 metres below the castle.

From there, a horizontal tunnel

would lead to a second, main shaft,

would lead to a second, main shaft,

which would carry Hitler to level -50,

the safest section of the complex.

- (Bogdan speaking other language)

NARRATOR: But above and beyond the protection of the Fuhrer,

what could be so important that they'd move him here,

what could be so important that they'd move him here,

to this seemingly isolated location?

There are numerous theories

about the real purpose of the Riese facility -

about the real purpose of the Riese facility -

its construction, its function,

and what role it would serve in the Nazi war plans.

There exists little in the way

There exists little in the way

of reliable information about the subject,

and research among historians and enthusiasts

is still ongoing.

is still ongoing.

ALEXANDRA: A lot of the Riese complex was left unfinished.

Some of it was filled with rubble at the end of the war.

Some of it was blown up, some of it caved in.

Some of it was blown up, some of it caved in.

There are all sorts of aspects of it

which we haven't yet even discovered.

NARRATOR: For many years,

the greatest secret of The Riese project

had been explored by geologist Piotr Kaluza.

had been explored by geologist Piotr Kaluza.

- (Piotr speaking other language)

NARRATOR: Currently, we are looking for the track paths,

which will help us find the tunnel buried by the collapse,

which will help us find the tunnel buried by the collapse,

to find out what it was used for and where it led.

- (machine beeping) - (Piotr speaking other language)

NARRATOR: Clearly, the tracks enter inside,

NARRATOR: Clearly, the tracks enter inside,

so, as they suspected,

the tracks turn heading towards the collapse.

- (speaking other language)

- (speaking other language)

NARRATOR: Was the top secret colossal project at Riese

the epicentre of Hitler and Speer's plan to save the Third Reich?

the epicentre of Hitler and Speer's plan to save the Third Reich?

Did they hope to develop and deploy here a superweapon

which would ensure Nazi Germany's final victory?

which would ensure Nazi Germany's final victory?

- (speaking other language)

NARRATOR: In order to discover the truth,

we will need to dig deeper.

The largest complex is Wlodarz.

The largest complex is Wlodarz.

It has three kilometres of underground tunnels.

The layout and room dimensions allow us

The layout and room dimensions allow us

to accurately determine the intended purpose of this facility.

It's much too large to be a human shelter.

It's much too large to be a human shelter.

Here is a plan of the underground factory in Konigsee,

from the German Federal Archives,

very similar to the structure of Wlodarz.

very similar to the structure of Wlodarz.

- (Lukasz speaking other language)

GUY: Just have a look at the size of Riese,

and those tunnels and those excavations and those bunkers.

and those tunnels and those excavations and those bunkers.

I mean, this is the size of a factory.

It's certainly a place where you could have easily constructed

a whole vengeance weapons programme, and there's just no doubt about it.

a whole vengeance weapons programme, and there's just no doubt about it.

NARRATOR: Germany had many innovations

that could change the course of the war,

if manufactured and deployed in sufficient numbers.

if manufactured and deployed in sufficient numbers.

- Nazi Germany was really technologically advanced.

NARRATOR: The Nazis pioneered aeronautics technology.

Jets, superfast aircraft,

and even planes capable of vertical takeoff were created.

and even planes capable of vertical takeoff were created.

- This was supposed to be a wonder weapon that would help win the war.

NARRATOR: But time was running out,

NARRATOR: But time was running out,

with the war progressively turning against the Nazis

with each passing day.

In August 1943,

In August 1943,

the Americans had destroyed the factory at Peenemunde

using heavy bombs.

Top secret technology had been developed

Top secret technology had been developed

in safer locations underground,

particularly those like the tunnel complex at Riese.

- (Lukasz speaking other language)

- (Lukasz speaking other language)

NARRATOR: These documents reveal the existence of a "special project"

and detailed Speer's account of a massive construction site,

and detailed Speer's account of a massive construction site,

requiring vast quantities of concrete and steel -

the largest building project ever undertaken in the Third Reich.

the largest building project ever undertaken in the Third Reich.

- (Lukasz speaking other language)

- (Lukasz speaking other language)

NARRATOR: That's equivalent to $6.5 billion today,

NARRATOR: That's equivalent to $6.5 billion today,

and over four times the expense

of Hitler's Wolf's Lair in Rastenburg.

- (Bogdan speaking other language)

- (Bogdan speaking other language)

VICTOR: One of the tunnels was built in a way

VICTOR: One of the tunnels was built in a way

that they could build a lab to research, for example,

explosives or nuclear power.

- (Lukasz speaking other language)

REPORTER: German scientists discover fission of the uranium nucleus,

bringing the Third Reich one step closer

to discovering the secret of the atomic bomb.

to discovering the secret of the atomic bomb.

NARRATOR: It was Strassmann and Hahn

who had first discovered nuclear reactivity in 1938.

who had first discovered nuclear reactivity in 1938.

In Berlin, the first prototype of harnessing this atomic power

In Berlin, the first prototype of harnessing this atomic power

was developed - the world's first nuclear reactor.

The war would change everything.

The war would change everything.

The race for the atomic bomb was on and, terrifyingly,

it looked as though Germany had a head start.

- There was a uranium mine near Riese,

which was mined all the way through the war.

This was supposed to be connected to the Wunderwaffe designs

of the idea that perhaps the Germans were developing an atomic weapon.

of the idea that perhaps the Germans were developing an atomic weapon.

NARRATOR: This has led to the theory

that the only way that Hitler could be persuaded to leave Berlin

was if he could seek refuge in a new super-complex,

was if he could seek refuge in a new super-complex,

deep below ground, allowing him to develop

the weapon he hoped could win the war, in relative safety.

At a strategic moment, with one decisive strike,

At a strategic moment, with one decisive strike,

he could convince the West to throw down its arms,

then force them to agree to the breakup of the Soviet Union.

then force them to agree to the breakup of the Soviet Union.

- (Lukasz speaking other language)

NARRATOR: But, as with so much of the hysteria

and dysfunction surrounding Hitler,

this was total fantasy.

this was total fantasy.

The reality was that the situation for the Nazis

was becoming more desperate by the day.

They were not only losing the war,

but also the race for atomic supremacy.

but also the race for atomic supremacy.

ADRIAN: German nuclear research had stalled.

They didn't get very far in their research into an atomic bomb,

They didn't get very far in their research into an atomic bomb,

and they didn't expect the Allies

to have got very far with their research.

- And we see by the Manhattan Project,

- And we see by the Manhattan Project,

the immense amount of money and material and scientists,

and actual cities were built for the Manhattan Project.

and actual cities were built for the Manhattan Project.

- (explosion) NARRATOR: The project was a research

and development undertaking during World War II

that produced the first nuclear weapons.

that produced the first nuclear weapons.

It was led by the United States under the direction

of the nuclear physicist Oppenheimer.

GUY: We have got to be really grateful to whoever that person is

that it wasn't Nazi Germany

that had the Manhattan Project.

REPORTER: United States bombers, bound for...

NARRATOR: The work undertaken at Riese was so critical

that it continued until after the siege of Berlin,

until the end of the war,

until the end of the war,

when the Red Army was on its doorstep.

ALEXANDRA: After the war, this area was taken over by the Soviet Union,

ALEXANDRA: After the war, this area was taken over by the Soviet Union,

and the Soviets were very keen on extracting and using

any uranium sources they possibly could, because they too, of course,

were developing their own nuclear project.

were developing their own nuclear project.

And the Soviets developed the nuclear bomb,

their own version, in 1949.

- (Bogdan speaking other language)

- (explosion ripples)

- (explosion ripples)

NARRATOR: If Hitler had not finally resolved to die a squalid death

with his mistress-turned-wife in a besieged Berlin bunker,

might he have contemplated a final escape

might he have contemplated a final escape

to the underground tunnels at Riese,

to mount a final desperate attack with his "wonder weapons"?

It's worth examining how safe and secure his hideout actually was,

It's worth examining how safe and secure his hideout actually was,

and whether it really could have survived

an all-out Allied bombing attack.

ALEXANDRA: Hitler slowly began to realise

that it was going to be more and more difficult

that it was going to be more and more difficult

to stay in the Wolf's Lair, as the Red Army approached.

And so he made the decision to move back to Berlin.

That's where he stayed for the rest of his life,

That's where he stayed for the rest of his life,

in the bunker underneath the Reich Chancellery.

GUY: You've really got to try to imagine

what it would've been like in that bunker,

what it would've been like in that bunker,

in the very last days of the war.

You know, it's hot,

it's damp, it's crowded.

it's damp, it's crowded.

People are scared, you know, there is fear everywhere,

and you can hear, above your head, all the time,

the bombing and the shelling coming from the Russians.

the bombing and the shelling coming from the Russians.

And Hitler's mental state by this point is...

ah, shall we say... it's not very healthy.

Frankly, by this point, he is mad.

ADRIAN: He was sitting in his bunker under Berlin.

The Soviets were within a few hundred metres of where he was,

and he really had no options left.

NARRATOR: According to eyewitness testimony,

NARRATOR: According to eyewitness testimony,

it was in the Berlin bunker that Hitler

first openly kissed his mistress, Eva Braun,

marrying her in a civil ceremony the day before his death.

marrying her in a civil ceremony the day before his death.

- This is a couple who are never gonna see daylight

ever again, in their lives.

ever again, in their lives.

You know, because Adolf Hitler and his new bride, Eva Hitler,

did not walk out of that room.

They killed themselves

They killed themselves

through a mixture of poison and gunshot.

Yeah, maybe. Maybe they said a final word to each other.

Maybe they said they loved each other.

Maybe they said they loved each other.

Ultimately, who cares?

The world had lost one of the most evil men who had ever been on it.

NARRATOR: But what if Hitler had not hidden

in a poorly fortified Berlin shelter,

where he took his last breath?

where he took his last breath?

What if he had heeded the pleas of Speer, among others,

and left the capital while he still could,

and had made his last stand from the Riese complex?

and had made his last stand from the Riese complex?

Could he have held out for significantly longer

than the end of April, 1945?

Security expert Adrian Weale

Security expert Adrian Weale

has been studying the hypotheticals.

- So one of the most significant advantages of the Riese complex,

- So one of the most significant advantages of the Riese complex,

in comparison, the Berlin bunker, is that it's dispersed.

That it's not just one single location.

There are a number of different elements to it,

There are a number of different elements to it,

which are spread out over a number of kilometres.

NARRATOR: For this reason, the best point of attack

for an Allied offensive would be to hit the main nerve:

for an Allied offensive would be to hit the main nerve:

the command of the Third Reich and Hitler himself.

The most valuable piece of artillery against superstructures

The most valuable piece of artillery against superstructures

and heavy fortifications at the time

was the British bunker-busting superbomb, Tallboy.

was the British bunker-busting superbomb, Tallboy.

- The Tallboy bomb weighed about five tons.

It was designed to be dropped from a great height.

It was designed to be dropped from a great height.

It was aerodynamic, it was armoured,

and it contained an enormous amount of explosives.

The idea was that it would penetrate deep into the ground,

The idea was that it would penetrate deep into the ground,

then detonate and it would have a similar effect to an earthquake.

The penetration of the Tallboy

The penetration of the Tallboy

was at least five metres through concrete.

The Tallboy bomb wouldn't have been completely effective

against the Riese structure.

NARRATOR: A heavy bombing campaign of this intensity

NARRATOR: A heavy bombing campaign of this intensity

would be sufficient to force Hitler and his staff to use

the escape routes from Ksiaz Castle to Osowka.

This would be a perfect opportunity to track them down

This would be a perfect opportunity to track them down

and launch a final assault

to capture Hitler and his entourage.

- I suspect the first attempt would be made

- I suspect the first attempt would be made

in a semi-conventional way, using commando troops,

SAS soldiers trained to a very high level.

Now, realistically, that's not going to work,

because the defences are so concentrated...

..because of the nature of the terrain around there.

..because of the nature of the terrain around there.

What we might then have is an opportunity to use the skills

of the Polish home army, partisans, the Cichociemni,

of the Polish home army, partisans, the Cichociemni,

who are, if you like, sort of special forces.

ALEXANDRA: They were meant to be parachuted into wherever it was,

ALEXANDRA: They were meant to be parachuted into wherever it was,

and to carry out sabotage.

ADRIAN: And they can probably get in much closer,

and that might give them an opportunity to use sarin,

and that might give them an opportunity to use sarin,

stolen from German stockpiles.

Sarin is an organophosphorus compound.

It's odourless. It's invisible.

It's absorbed by touch or by inhaling,

and it kills you very nastily and very quickly.

and it kills you very nastily and very quickly.

So using the gravity ventilation system in the Riese complex,

you would actually be able to circulate it quite quickly

you would actually be able to circulate it quite quickly

from the top of the complex, right down into the lowest levels,

where normally you'd expect to be completely protected

from attack from outside.

from attack from outside.

VICTOR: All the particulars

will flow inside the bunker uncontrolled.

will flow inside the bunker uncontrolled.

NARRATOR: Should this also fail,

would it be possible to use the ultimate weapon:

would it be possible to use the ultimate weapon:

an atomic device?

- Hitler can then evacuate to the Osowka,

which is specially designed for him,

which is specially designed for him,

a kind of last bolthole.

That's in the mountains. That really isn't

going to be possible to attack in a conventional way.

going to be possible to attack in a conventional way.

Potentially, by then, in this scenario, the Little Boy is ready.

NARRATOR: Could the massive underground fortifications

and bunkers survive a direct hit

and bunkers survive a direct hit

from a 15 kiloton atomic payload?

- The Little Boy bomb, if you detonate it on the ground,

- The Little Boy bomb, if you detonate it on the ground,

close to its target,

then the blast wave would create an enormous hole,

and would be good enough to destroy any of the structures

and would be good enough to destroy any of the structures

that were part of the Riese complex.

NARRATOR: So let's play out these various scenarios

in order to see how safe the most powerful hideout,

in the last rampart of the greatest criminal in history,

in the last rampart of the greatest criminal in history,

could really be.

To ensure that Hitler has no chance of escape,

To ensure that Hitler has no chance of escape,

it is imperative to attack both facilities -

Ksiaz Castle and Osowka - simultaneously.

Ksiaz Castle and Osowka - simultaneously.

The approach of commandos is preceded

by the heavy shelling of Ksiaz Castle.

Commandos secure escape routes from the castle,

Commandos secure escape routes from the castle,

while a group of sappers destroy the exit

from the escape tunnels, leading to shelters under the castle.

from the escape tunnels, leading to shelters under the castle.

- (heavy breathing)

NARRATOR: SAS commandos hit security locks and machine gunfire.

NARRATOR: SAS commandos hit security locks and machine gunfire.

This is the signal for a group of Cichociemni,

the lead Polish commando and guerrillas, to sabotage.

the lead Polish commando and guerrillas, to sabotage.

Let the deadly sarin into the ventilation shaft.

Sarin should kill everyone in Ksiaz Castle.

However, if Hitler manages to escape Osowka,

However, if Hitler manages to escape Osowka,

then plan B is prepared.

The Allies call on a B-29 bomber

carrying Little Boy, an atomic device.

carrying Little Boy, an atomic device.

The bomb hits the mountainside at the entrance to the tunnel.

The bomb hits the mountainside at the entrance to the tunnel.

The enormous force and radiation

reduces the tunnel complex to rubble,

and destroys everything inside and out,

and destroys everything inside and out,

within a blast radius of over a kilometre.

Nothing, not even Riese,

survives that.

survives that.

- Had the Riese complex been finished,

and had Hitler been able to get there

when the Russians were approaching,

it would have delayed the end of the Second World War,

but it wouldn't have prevented it.

Ultimately, the Russians, or the Western Allies,

Ultimately, the Russians, or the Western Allies,

whoever got to it first,

would have worked out how to get inside and clear the whole thing.

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